Effects of metformin on learning and memory behaviors and brain mitochondrial functions in high fat diet induced insulin resistant rats.

Abstract

AIM:

Metformin is a first line drug for the treatment of type 2 diabetes mellitus (T2DM). Our previous study reported that high-fat diet (HFD) consumption caused not only peripheral and neuronal insulin resistance, but also induced brain mitochondrial dysfunction as well as learning impairment. However, the effects of metformin on learning behavior and brain mitochondrial functions in HFD-induced insulin resistant rats have never been investigated.

MAIN METHODS:

Thirty-two male Wistar rats were divided into two groups to receive either a normal diet (ND) or a high-fat diet (HFD) for 12weeks. Then, rats in each group were divided into two treatment groups to receive either vehicle or metformin (15mg/kg BW twice daily) for 21days. All rats were tested for cognitive behaviors using the Morris water maze (MWM) test, and blood samples were collected for the determination of glucose, insulin, and malondialdehyde. At the end of the study, animals were euthanized and the brain was removed for studying brain mitochondrial function and brain oxidative stress.